Average Weather in December in Attalens Switzerland
Daily high temperatures decrease by 3°F, from 40°F to 36°F, rarely falling below 28°F or exceeding 48°F.
Daily low temperatures decrease by 3°F, from 30°F to 27°F, rarely falling below 17°F or exceeding 38°F.
For reference, on August 4, the hottest day of the year, temperatures in Attalens typically range from 56°F to 75°F, while on January 19, the coldest day of the year, they range from 26°F to 36°F.
Average High and Low Temperature in December
The figure below shows you a compact characterization of the hourly average temperatures for the quarter of the year centered on December. The horizontal axis is the day, the vertical axis is the hour of the day, and the color is the average temperature for that hour and day.
Average Hourly Temperature in December
The month of December in Attalens experiences essentially constant cloud cover, with the percentage of time that the sky is overcast or mostly cloudy remaining about 57% throughout the month. The highest chance of overcast or mostly cloudy conditions is 58% on December 30.
The clearest day of the month is December 17, with clear, mostly clear, or partly cloudy conditions 44% of the time.
For reference, on May 8, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 60%, while on July 23, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 64%.
Cloud Cover Categories in December
0% clear 20% mostly clear 40% partly cloudy 60% mostly cloudy 80% overcast 100%
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. In Attalens, the chance of a wet day over the course of December is essentially constant, remaining around 33% throughout.
For reference, the year's highest daily chance of a wet day is 43% on May 27, and its lowest chance is 27% on March 3.
Over the course of December in Attalens, the chance of a day with only rain remains an essentially constant 22% throughout, the chance of a day with mixed snow and rain remains an essentially constant 6% throughout, and the chance of a day with only snow remains an essentially constant 4% throughout.
Probability of Precipitation in December
The average sliding 31-day rainfall during December in Attalens is essentially constant, remaining about 2.9 inches throughout, and rarely exceeding 5.5 inches or falling below 0.7 inches.
Average Monthly Rainfall in December
We report snowfall in liquid-equivalent terms. The actual depth of new snowfall is typically between 5 and 10 times the liquid-equivalent amount, assuming the ground is frozen. As with rainfall, we consider the liquid-equivalent snowfall accumulated over a sliding 31-day period centered around each day.
The average sliding 31-day liquid-equivalent snowfall during December in Attalens is essentially constant, remaining about 0.5 inches throughout, and rarely exceeding 1.5 inches or falling below -0.0 inches.
The highest average 31-day liquid-equivalent accumulation is 0.5 inches on December 28.
Average Monthly Liquid-Equivalent Snowfall in December
Over the course of December in Attalens, the length of the day is essentially constant. The shortest day of the month is December 21, with 8 hours, 34 minutes of daylight and the longest day is December 1, with 8 hours, 52 minutes of daylight.
Hours of Daylight and Twilight in December
The earliest sunrise of the month in Attalens is 7:55 AM on December 1 and the latest sunrise is 21 minutes later at 8:16 AM on December 31.
The earliest sunset is 4:45 PM on December 11 and the latest sunset is 10 minutes later at 4:54 PM on December 31.
Daylight saving time is observed in Attalens during 2018, but it neither starts nor ends during December, so the entire month is in standard time.
For reference, on June 21, the longest day of the year, the Sun rises at 5:39 AM and sets 15 hours, 50 minutes later, at 9:29 PM, while on December 21, the shortest day of the year, it rises at 8:13 AM and sets 8 hours, 34 minutes later, at 4:47 PM.
Sunrise & Sunset with Twilight in December
The chance that a given day will be muggy in Attalens is essentially constant during December, remaining around 0% throughout.
For reference, on July 21, the muggiest day of the year, there are muggy conditions 0% of the time, while on January 1, the least muggy day of the year, there are muggy conditions 0% of the time.
Humidity Comfort Levels in December
dry 55°F comfortable 60°F humid 65°F muggy 70°F oppressive 75°F miserable
The average hourly wind speed in Attalens is essentially constant during December, remaining within 0.2 miles per hour of 5.9 miles per hour throughout.
For reference, on April 3, the windiest day of the year, the daily average wind speed is 6.2 miles per hour, while on August 10, the calmest day of the year, the daily average wind speed is 5.1 miles per hour.
Average Wind Speed in December
Wind Direction in December
The growing season in Attalens typically lasts for 6.6 months (202 days), from around April 11 to around October 30, rarely starting before March 22 or after May 3, and rarely ending before October 9 or after November 23.
The month of December in Attalens is very likely fully outside of the growing season, with the chance that a given day is in the growing season gradually decreasing from 5% to 0% over the course of the month.
Time Spent in Various Temperature Bands and the Growing Season in December
The average accumulated growing degree days in Attalens are essentially constant during December, remaining around 1,868°F throughout.
Growing Degree Days in December
The average daily incident shortwave solar energy in Attalens is essentially constant during December, remaining within 0.1 kWh of 1.4 kWh throughout.
The lowest average daily incident shortwave solar energy during December is 1.3 kWh on December 24.
Average Daily Incident Shortwave Solar Energy in December
For the purposes of this report, the geographical coordinates of Attalens are 46.506 deg latitude, 6.850 deg longitude, and 2,418 ft elevation.
The topography within 2 miles of Attalens contains large variations in elevation, with a maximum elevation change of 2,100 feet and an average elevation above sea level of 2,574 feet. Within 10 miles contains large variations in elevation (5,404 feet). Within 50 miles also contains extreme variations in elevation (14,603 feet).
The area within 2 miles of Attalens is covered by cropland (62%) and trees (31%), within 10 miles by cropland (31%) and trees (29%), and within 50 miles by trees (34%) and cropland (21%).
This report illustrates the typical weather in Attalens year round, based on a statistical analysis of historical hourly weather reports and model reconstructions from January 1, 1980 to December 31, 2016.
Temperature and Dew Point
There are 4 weather stations near enough to contribute to our estimation of the temperature and dew point in Attalens.
For each station, the records are corrected for the elevation difference between that station and Attalens according to the International Standard Atmosphere , and by the relative change present in the MERRA-2 satellite-era reanalysis between the two locations.
The estimated value at Attalens is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Attalens and a given station.
The stations contributing to this reconstruction are: Sion (31%, 48 kilometers, southeast); Neuchatel (27%, 56 kilometers, north); Aéroport Genève-Cointrin (21%, 64 kilometers, southwest); and Bern-Belp Airport (21%, 67 kilometers, northeast).
All other weather data, including cloud cover, precipitation, wind speed and direction, and solar flux, come from NASA's MERRA-2 Modern-Era Retrospective Analysis . This reanalysis combines a variety of wide-area measurements in a state-of-the-art global meteorological model to reconstruct the hourly history of weather throughout the world on a 50-kilometer grid.
Time zones for aiports and weather stations are provided by AskGeo.com .